A chuckle escape Leon as Aeria stated simply that the train was moving. "I suppose it is," he had said to her with a small grin when she bit her lip, looking back towards Tollnak as he began to speak. Leon nodded as Tollnak spoke. Everything that he shared with Leon were perfectly valid concerns, though he did plan to have more extensive knowledge in nerve repair before he took a crack at Tollnak. He had a solid understanding of mutations and how they interacted with the body and there wasn't really that much of a worry about disrupting the guy's mutation. Though, on the off chance that the worse happened, Tollnak wouldn't be able to operate his false arm. Leon would never be able to face people again if he ruined Tollnak's gift. 

"You're right to be worried," Leon admitted, his voice slow as if he wear caught in thought. "I can't promise everything would go off without a hitch," he paused, biting his lip, "I've been learning how to repair nerves, among other things, for the past few years and I think I'm on the verge of a breakthrough. If I find that breakthrough, I'll show you what I've been working on and let you decide for yourself whether or not you want me to work on your eyes." Tollnak seemed to be the first to notice Keita, who may have been standing their for quite awhile at this point. When Tollnak spoke up, Leon nodded. "Yeah," he said. Yeah was the best he could do at a moment like this. Confronting a ghost of one's past was always daunting. The fact that the past was unaware it was but a ghost now made it all the harder. 

"Try not to get on too well without me, eh? I'd hate to miss out on the fun." Leon smiled at the two, standing up. With his right hand he fiddled with his bowtie slightly, adjusting the way his collar hugged his neck, bringing it up ever so slightly. He left arm hung at his side, still as stone. "Keita," Leon said as he stepped out into the car's aisle, "You wanna talk?" Leon began to walk away from the group, away from the boy who hid his bug-like mandibles, away from the other boy who seemed to be particularly unsocial. He stopped at the door, sliding it open and stepped through, letting it seal behind him and took his place near the center of the empty train car, leaning against a support beam in the center of the aisle. "So, what's up doc?" Leon would call out, the moment the doors opened and Keita stepped in. However long it took Keita was entirely his prerogative. Leon was made of time.